The present invention relates to a thrust reverser for a turbofan engine, more particularly a thrust reverser for such a turbofan engine having a very high bypass ratio.
Turbofan engines are, of course, well known in the art and typically comprise a gas turbine engine having a housing extending around the engine, and a fan housing radially spaced from and extending around the gas turbine engine housing so as to define a cold flow air duct between the fan housing and the gas turbine engine housing. A turbofan, driven by the gas turbine engine and having one or more fan stages, draws air into the cold flow air duct through an inlet and directs the air outwardly in a downstream direction through a cold flow exhaust opening.
It is also known to make such engines having thrust reversers which deflect the flow of the cold flow air in order to provide the thrust reversing force. These devices have proven particularly effective in such turbofan engines having a high bypass ratio.
Typically, the known thrust reversers comprise displaceable baffle elements which may be extended into the cold flow air stream so as to redirect the air stream and provide a thrust reversing force to the air frame. When the turbofan engine operates in a forward thrust mode, the displaceable baffles are retracted such that they generally assume the surface configuration of the gas turbine engine housing. Examples of such known thrust reversers can be found in French Patents 1,479,131; 2,625,261; and 2,650,861.
The known thrust reversers, however, have proven to be bulky, heavy and have not permitted the engine structure to have an external diameter sufficient to provide requisite ground clearance, especially in such turbofan engines having a very high bypass ratio.